A Hot Wheels car of mass 0.081 kg starts at a height of 1.42 m and goes through a loop with a height of 0.38 m with a radius of 0.16 m along a track of length 3.02 m. The car barely makes it through the loop. Since, Work = Force x distance, what is the force of friction acting upon the car?

Question

A Hot Wheels car of mass 0.081 kg starts at a height of 1.42 m and goes through a loop with a height of 0.38 m with a radius of 0.16 m along a track of length 3.02 m.  The car barely makes it through the loop.  Since, Work = Force x distance, what is the force of friction acting upon the car?